1. Field of the Invention
The present invention relates to a cleaning apparatus that cleans the surface of an image carrying body by removing toner remaining thereon after transferring a toner image to paper, and to an image forming apparatus provided with the cleaning apparatus.
2. Description of Related Art
In electrophotographic image forming apparatuses, a widely-used method of transferring a toner image to paper is as follows. A transfer region is formed by making a photoconductor drum, which is an image carrying body, and a transfer roller, which is a transfer member, come into contact with each other, or by bringing them close to each other, and then paper is inserted through the transfer region thus formed, thereby transferring a toner image formed on the surface of the photoconductor drum to paper.
With such a transfer method, however, residual toner may result because there is a possibility that a small amount of toner is not transferred to paper and remains on the surface of the photoconductor drum after a toner image is transferred to the paper. The residual toner remaining on the surface of the photoconductor drum hampers the formation of next new images, and therefore should be cleaned therefrom. As cleaning methods for the above-described purposes, a method of recovering the residual toner by pressing a rotating member such as a cleaning roller or a rotating brush against the surface of the photoconductor drum and moving the residual toner to the rotating member, a method of scraping the residual toner off the surface of the photoconductor drum by making a cleaning blade come into contact therewith, and a cleaning method obtained by combining the above two methods are widely known.
On the other hand, when an amorphous silicon photoconductor is used as the photoconductor, there often occurs image deletion that disturbs an electrostatic latent image by absorption of moisture by electrical discharge products formed on the surface of the photoconductor. It is for this reason that a cleaning method is known that not only removes residual toner from the surface of the photoconductor by using a cleaning roller, which is a rotating member, in combination with a cleaning blade, but also scrubs the electrical discharge products off the surface of the photoconductor with toner in which a small amount of abrasive is mixed by making the cleaning roller carry a small amount of toner.
Examples of these cleaning apparatuses that remove the residual toner on the surface of the photoconductor drum by using a rotating member or a cleaning blade are disclosed in JP-A-2003-98924 (hereinafter referred to as Patent Publication 1) and JP-A-2004-101816 (hereinafter referred to as Patent Publication 2).
In the cleaning apparatus disclosed in Patent Publication 1, toner removed from the surface of a photoconductor drum and then attached to the surface of a cleaning roller is scraped therefrom by a scraper that is brought into contact with the cleaning roller by pressurizing, thereby permitting the toner thus scraped to move in a space provided between the cleaning roller and a discharging member. With this structure, however, when the toner that has started moving from the cleaning roller toward the discharging member does not reach the discharging member, it accumulates on the surface of the cleaning roller. As a result, the toner used for cleaning constantly comes into contact with the surface of the photoconductor drum, which may lead, for example, to solidification of toner or toner adhesion to the surface of the drum. Worse yet, there is a possibility that the contact pressure between the cleaning roller or the cleaning blade and the photoconductor drum increases due to accumulation of toner, affecting the cleaning performance of these members.
In the cleaning apparatus disclosed in Patent Publication 2, toner removed from the surface of the photoconductor drum and then attached to a cleaning brush is made to fly toward toner recovering and transporting means (a discharging member) by flipping the brush fibers. With this structure, however, when the toner flying from the cleaning brush does not reach the toner recovering and transporting means, it falls to the surface of the cleaning brush again, and then accumulates on the surface of the cleaning brush or the photoconductor drum. Therefore, there is a high possibility that the same problem as in the case of Patent Publication 1 arises.